1. Field of the Invention
The present invention relates to wringers such as for use in clean rooms, and particularly to a versatile, wringer that can wring a variety of types and sizes of mops, wipes, sponges and other wringable materials.
2. Description of Related Art
Certain pharmaceuticals, electronics and other specialized goods must be manufactured in contamination-free "clean rooms" which are kept free from impurities such as dust and microorganisms. Similarly, hospitals maintain their operating rooms as "clean rooms", which must be kept free form microorganisms and dust particles, and all reusable items must be sterilized in high-heat autoclaves prior to reuse in the sterile environment of an operating room.
In typical procedures for maintaining the contamination-free environment of a clean room, cleaning crews that regularly mop and wipe the room use a bucket of cleaning solution, a mop and a wringer along with sponges. Sponges are usually rinsed and squeezed out by hand into the bucket of cleaning solution, while the mop is typically rinsed in the bucket and then wrung out with the wringer.
The most common type of wringer is the downward gear press wringer. The wringer uses levers, gears and springs for moving two parallel bars to converge downward, thereby applying a downward force along two line segments on the mop head. The wringer has a perforated pan at the bottom to permit drainage.
Standard wringers generally do not apply a uniform wringing pressure to a mop or other wringable items. For instance, the gear press wringer typically applies pressure only where the bars contact the mop. However, for a string mop, for example, or a flap mop, placed on the perforated pan of the wringer, the strings take whatever shape they can given the shape of the sides and bottom of the wringer, but the strings will not necessarily conform in every respect to the shape of the wringer. Thereafter, the rigid parallel bars of the wringer contact and press only those parts of the mop which are in contact with the sides of the wringer. However, for those parts of the string mop which may move or readjust during the process of wringing, such as by squeezing out the sides or moving toward the bottom of the wringer, the full wringing action may not be applied to those parts. Therefore, a uniform wringing of solution from the mop may not be achieved because of happenstance variations in the shape of the strings.
Typical wringers such as the gear press wringer are also limited in the number of different configurations of mops that can be accommodated in the wringer. A given wringer is typically designed for a certain type and size of mop and would not easily accommodate mops having other shapes and sizes. For example, a mop having a large, square sponge head may not fit easily into a wringer designed for small string mops. Even if a wringer could accept different types of mops, the performance of the wringer in extracting solvent is generally better for one type of mop than the others. Therefore, typical wringers are not very versatile.
Additionally, most wringers have a minimum item size because the gear press will only travel so far. Accordingly, the wringers will not clean small wipes or sponges.
Typical wringers are difficult to clean. Dirt particles get caught in the cracks and corners of the assembly, which must then be hosed down. If the wringer is not regularly cleaned, accumulating dust and dirt fall down into the cleaning solution and work their way back onto surfaces of the clean room.
A further problem with existing wringers is that some typically require lubricants for proper operation. Lubricants from the wringer may then end up in the cleaning solution and then the clean room. Moreover, wringers used to clean operating rooms must be sterilized in an autoclave. The moving parts of the wringer are normally coated with grease or oil to reduce friction. In the high heat environment of an autoclave, the grease and/or oil flows very easily and drips onto the autoclave and migrates from the area that needs the lubrication. The wringer then must be re-lubricated before it can be used again.
Grease and oil are problematic in other ways, such as getting into the cleaning solution and eventually onto the floor and walls of the clean room. Unfortunately, to eliminate the lubricant would allow moving metal parts such as shafts to grind against adjoining metal surfaces, creating metal particles which drop down into the cleaning solution and then into the clean room.